Question: $ { \left[\begin{array}{rrr}{1} & {-1} & {3} \\ {1} & {4} & {2}\end{array}\right]+\left[\begin{array}{rrr}{4} & {-1} & {4} \\ {-1} & {1} & {2}\end{array}\right] = {?} } $
Solution: To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{rrr}{1}+{4} & {-1}+{-1} & {3}+{4} \\ {1}+{-1} & {4}+{1} & {2}+{2}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{5} & {-2} & {7} \\ {0} & {5} & {4}\end{array}\right]}$